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Greenwich, London, England
Royal Observatory and National Maritime Museum
It’s no exaggeration to say that Greenwich is the center of the world: after all, the Prime Meridian of the Earth runs right through the Royal Observatory at Greenwich. A meridian is an imaginary north/south line that passes through both of the Earth’s poles; the Prime Meridian defines 0° of longitude and the time basis for all the world’s clocks. Greenwich Mean Time is now officially called Universal Time.
The Royal Observatory has been at Greenwich since 1675 and was of great importance in maintaining Britain’s naval power: observations of planets, moons, and stars were needed for the nautical almanacs used for navigation. Close to the Royal Observatory is the National Maritime Museum, which contains the clock that revolutionized navigation in 1759—John Harrison’s H4 marine chronometer.
Also on display at the National Maritime Museum are three clocks that Harrison built prior ...